The American Civil Liberties Union announced a legislative effort Tuesday to limit local police involvement in immigration enforcement, a practice the group called wasteful and counterproductive.

Sen. Victor Ramirez, D-Prince George's, will lead the push to enact the Maryland Trust Act, state ACLU leaders told immigration reform advocates in Hyattsville. Ramirez previously sponsored successful bills enabling people without legal permission to be in the country to continue obtaining Maryland driver's licenses and allowing those meeting certain conditions to pay in-state college tuition.

Ramirez didn't immediately respond to queries from The Associated Press. His chief of staff said Monday that details of the bill weren't complete.

The bill would limit police powers to hold people on immigration detainers issued by the U.S. Immigration and Customs Enforcement agency, ACLU said.

The detainers, also called "immigration holds," authorize police to hold for an additional 48 hours people who have been convicted or charged with crimes until ICE officials can pick them up. The ICE issues a detainer when a person's fingerprints, uploaded by state or local police to an FBI criminal database, are automatically checked against immigration files and trigger an investigation.

The ACLU said local police waste resources and generate distrust among immigrants by honoring immigration detainers. The detainers "are lodged mostly against people charged with traffic violations or misdemeanors and do not serve any discernible local law enforcement public safety function," the group said in a report.

"The ACLU is calling on Maryland to join other states in deciding that complying with these requests is an inefficient use of our limited law enforcement resources and results only in ripping apart our communities," ACLU attorney Sirine Shebaya said.

Brad Botwin, director of the pro-enforcement group Help Save Maryland, said the detainers extend the government's ability to find and deport the people in question, regardless of what other offenses they may have committed.

"The bottom line is, they should not be here," Botwin said. "They are using my schools, my social services, my hospitals without legal presence, and therefore they can and should be detained and removed."

The Maryland attorney general's office said in an Oct. 31 advisory letter to Ramirez that state and local jurisdictions can decide whether to honor the detainers. That view jibes with an Indiana federal court ruling and a California attorney general's opinion. It conflicts with a Pennsylvania federal court ruling that an immigration detainer is a mandatory hold order.